1. Field of the Invention
The invention relates to a transport bin in an X-ray inspection system, an X-ray inspection system that has at least one transport bin, and a method for security inspection.
2. Description of the Background Art
German patent application DE 10 2009 015 606, which is incorporated herein by reference, describes X-ray systems that are used to inspect the hand luggage of airline passengers for illegal or hazardous contents. For this purpose, an X-ray image of the luggage item to be inspected is produced at an initial inspection station with an X-ray device. Luggage items that cannot be unambiguously classified as non-suspicious based on the X-ray image are opened and rechecked by another operator. For this purpose, the operator at the recheck station has a display screen on which the previously produced X-ray image is displayed. Since the initial inspection station with the X-ray device and the recheck station generally are spatially separated, the problem arises of rapidly and reliably identifying and displaying at the recheck station the X-ray image corresponding to the luggage item to be inspected.
The objects to be inspected are placed in transport bins that have an identification device permanently attached to the bin. The identification device contains an unambiguous identifier for the transport bin. The identification device is, for example, an RFID transmitter, in particular an RFID transponder, a bar code, or lead symbols. The identifier of the transport bin during the inspection process also uniquely identifies the luggage item.
The X-ray system includes, among other things, an initial inspection station, a recheck station, and at least one transport bin. Each transport bin has an unambiguous identifier. The initial inspection station has an X-ray device for creating an X-ray image, a device for reading out the identification device of the transport bin, and a device for associating the X-ray image with the transport bin. The X-ray image is associated with the transport bin through the identifier of the transport bin. The transport bin identifier is ascertained in that the identification device is read out.
The X-ray device comprises an X-ray apparatus with at least one X-ray source and at least one X-ray detector in a radiopaque housing, as well as an operating and display apparatus. An X-ray image of the luggage item is computed from the output signal of the X-ray detector and is displayed on the display apparatus.
The device for reading out the identification device of the transport bin can be, for example, an RFID receiver or a bar code reader. These devices are advantageously located in the vicinity of the X-ray apparatus. Alternatively or in addition, the device for reading out the identification device of the transport bin is an image processing routine that extracts the identifier from the X-ray image.
The recheck station has a device for reading out the identification device of the transport bin, and a device for displaying the X-ray image associated with the transport bin. The display device preferably is connected to the X-ray device of the initial inspection station in order to retrieve from there the X-ray image to be displayed.
The device for reading out the identification device at the recheck station is, for example, an RFID receiver or a bar code reader. Alternatively or in addition, the device for reading out the identification device of the transport bin is an optical input device such as a camera. The input device either recognizes the lead symbols directly, or recognizes a legend that contains the same identifier as the lead symbols.
During the security inspection of an object, the object is first placed in a transport bin. Next, an X-ray image of the object is made and evaluated, for example by an operator. In addition, the identifier of the transport bin is read and automatically associated with the corresponding X-ray image. Then the transport bin is transported to a recheck station, the identifier of the transport bin is determined, and the X-ray image associated with the transport bin's identifier is displayed.
In the conventional systems, under certain circumstances errors can occur in associating the bins, which is to say the luggage items, with the corresponding X-ray images at the recheck stations, when multiple X-ray inspection units are used in parallel and the transport bins are exchanged among them. If an image is produced with a transport bin at a first unit, and the bin is subsequently used in a second unit, then it can occur during a recheck in the second unit that either the last image recorded in the first unit with the transport bin is displayed, or that two transport bins with the same identifier are present in the second unit.